Variant selection in transformation texture from the β to α phase in Cu–40 mass% Zn alloy

Abstract

The rolling texture and variant selection in texture during the phase transformation from β to α in Cu–40 mass% Zn were investigated using X-ray back reflection and electron back-scatter diffraction pattern (EBSP) techniques. The rolling texture of the β parent phase, before the phase transformation, was composed of {111}〈1 1 ̄ 0〉, {001}〈110〉 and {111}〈 1 ̄ 1 ̄ 2〉. Variant selection occurred during the β to α phase transformation from the cold-rolled parent β phase, even when the phase transformation following the Kurdjumov–Sachs relationship was controlled by a diffusion process. The variant selection was related to the Bain distortion for each α variant during the phase transformation from the β to α phase. A limited set of α variants was chosen to minimize the residual stress induced in the deformed β parent phase by the Bain distortion. The type of selected variants changed with the rolling texture of β parent phase. The selectivity of specific variants increased and was stimulated by both annealing temperature and rolling reduction.